1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or http://www.opensolaris.org/os/licensing. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2012, 2016 by Delphix. All rights reserved. 24 */ 25 26 #include <sys/zfs_context.h> 27 #include <sys/dmu_objset.h> 28 #include <sys/dmu_traverse.h> 29 #include <sys/dsl_dataset.h> 30 #include <sys/dsl_dir.h> 31 #include <sys/dsl_pool.h> 32 #include <sys/dnode.h> 33 #include <sys/spa.h> 34 #include <sys/zio.h> 35 #include <sys/dmu_impl.h> 36 #include <sys/sa.h> 37 #include <sys/sa_impl.h> 38 #include <sys/callb.h> 39 #include <sys/zfeature.h> 40 41 int32_t zfs_pd_bytes_max = 50 * 1024 * 1024; /* 50MB */ 42 boolean_t send_holes_without_birth_time = B_TRUE; 43 44 typedef struct prefetch_data { 45 kmutex_t pd_mtx; 46 kcondvar_t pd_cv; 47 int32_t pd_bytes_fetched; 48 int pd_flags; 49 boolean_t pd_cancel; 50 boolean_t pd_exited; 51 zbookmark_phys_t pd_resume; 52 } prefetch_data_t; 53 54 typedef struct traverse_data { 55 spa_t *td_spa; 56 uint64_t td_objset; 57 blkptr_t *td_rootbp; 58 uint64_t td_min_txg; 59 zbookmark_phys_t *td_resume; 60 int td_flags; 61 prefetch_data_t *td_pfd; 62 boolean_t td_paused; 63 uint64_t td_hole_birth_enabled_txg; 64 blkptr_cb_t *td_func; 65 void *td_arg; 66 boolean_t td_realloc_possible; 67 } traverse_data_t; 68 69 static int traverse_dnode(traverse_data_t *td, const dnode_phys_t *dnp, 70 uint64_t objset, uint64_t object); 71 static void prefetch_dnode_metadata(traverse_data_t *td, const dnode_phys_t *, 72 uint64_t objset, uint64_t object); 73 74 static int 75 traverse_zil_block(zilog_t *zilog, blkptr_t *bp, void *arg, uint64_t claim_txg) 76 { 77 traverse_data_t *td = arg; 78 zbookmark_phys_t zb; 79 80 if (BP_IS_HOLE(bp)) 81 return (0); 82 83 if (claim_txg == 0 && bp->blk_birth >= spa_first_txg(td->td_spa)) 84 return (0); 85 86 SET_BOOKMARK(&zb, td->td_objset, ZB_ZIL_OBJECT, ZB_ZIL_LEVEL, 87 bp->blk_cksum.zc_word[ZIL_ZC_SEQ]); 88 89 (void) td->td_func(td->td_spa, zilog, bp, &zb, NULL, td->td_arg); 90 91 return (0); 92 } 93 94 static int 95 traverse_zil_record(zilog_t *zilog, lr_t *lrc, void *arg, uint64_t claim_txg) 96 { 97 traverse_data_t *td = arg; 98 99 if (lrc->lrc_txtype == TX_WRITE) { 100 lr_write_t *lr = (lr_write_t *)lrc; 101 blkptr_t *bp = &lr->lr_blkptr; 102 zbookmark_phys_t zb; 103 104 if (BP_IS_HOLE(bp)) 105 return (0); 106 107 if (claim_txg == 0 || bp->blk_birth < claim_txg) 108 return (0); 109 110 SET_BOOKMARK(&zb, td->td_objset, lr->lr_foid, 111 ZB_ZIL_LEVEL, lr->lr_offset / BP_GET_LSIZE(bp)); 112 113 (void) td->td_func(td->td_spa, zilog, bp, &zb, NULL, 114 td->td_arg); 115 } 116 return (0); 117 } 118 119 static void 120 traverse_zil(traverse_data_t *td, zil_header_t *zh) 121 { 122 uint64_t claim_txg = zh->zh_claim_txg; 123 zilog_t *zilog; 124 125 /* 126 * We only want to visit blocks that have been claimed but not yet 127 * replayed; plus, in read-only mode, blocks that are already stable. 128 */ 129 if (claim_txg == 0 && spa_writeable(td->td_spa)) 130 return; 131 132 zilog = zil_alloc(spa_get_dsl(td->td_spa)->dp_meta_objset, zh); 133 134 (void) zil_parse(zilog, traverse_zil_block, traverse_zil_record, td, 135 claim_txg); 136 137 zil_free(zilog); 138 } 139 140 typedef enum resume_skip { 141 RESUME_SKIP_ALL, 142 RESUME_SKIP_NONE, 143 RESUME_SKIP_CHILDREN 144 } resume_skip_t; 145 146 /* 147 * Returns RESUME_SKIP_ALL if td indicates that we are resuming a traversal and 148 * the block indicated by zb does not need to be visited at all. Returns 149 * RESUME_SKIP_CHILDREN if we are resuming a post traversal and we reach the 150 * resume point. This indicates that this block should be visited but not its 151 * children (since they must have been visited in a previous traversal). 152 * Otherwise returns RESUME_SKIP_NONE. 153 */ 154 static resume_skip_t 155 resume_skip_check(traverse_data_t *td, const dnode_phys_t *dnp, 156 const zbookmark_phys_t *zb) 157 { 158 if (td->td_resume != NULL && !ZB_IS_ZERO(td->td_resume)) { 159 /* 160 * If we already visited this bp & everything below, 161 * don't bother doing it again. 162 */ 163 if (zbookmark_subtree_completed(dnp, zb, td->td_resume)) 164 return (RESUME_SKIP_ALL); 165 166 /* 167 * If we found the block we're trying to resume from, zero 168 * the bookmark out to indicate that we have resumed. 169 */ 170 if (bcmp(zb, td->td_resume, sizeof (*zb)) == 0) { 171 bzero(td->td_resume, sizeof (*zb)); 172 if (td->td_flags & TRAVERSE_POST) 173 return (RESUME_SKIP_CHILDREN); 174 } 175 } 176 return (RESUME_SKIP_NONE); 177 } 178 179 static void 180 traverse_prefetch_metadata(traverse_data_t *td, 181 const blkptr_t *bp, const zbookmark_phys_t *zb) 182 { 183 arc_flags_t flags = ARC_FLAG_NOWAIT | ARC_FLAG_PREFETCH; 184 185 if (!(td->td_flags & TRAVERSE_PREFETCH_METADATA)) 186 return; 187 /* 188 * If we are in the process of resuming, don't prefetch, because 189 * some children will not be needed (and in fact may have already 190 * been freed). 191 */ 192 if (td->td_resume != NULL && !ZB_IS_ZERO(td->td_resume)) 193 return; 194 if (BP_IS_HOLE(bp) || bp->blk_birth <= td->td_min_txg) 195 return; 196 if (BP_GET_LEVEL(bp) == 0 && BP_GET_TYPE(bp) != DMU_OT_DNODE) 197 return; 198 199 (void) arc_read(NULL, td->td_spa, bp, NULL, NULL, 200 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); 201 } 202 203 static boolean_t 204 prefetch_needed(prefetch_data_t *pfd, const blkptr_t *bp) 205 { 206 ASSERT(pfd->pd_flags & TRAVERSE_PREFETCH_DATA); 207 if (BP_IS_HOLE(bp) || BP_IS_EMBEDDED(bp) || 208 BP_GET_TYPE(bp) == DMU_OT_INTENT_LOG) 209 return (B_FALSE); 210 return (B_TRUE); 211 } 212 213 static int 214 traverse_visitbp(traverse_data_t *td, const dnode_phys_t *dnp, 215 const blkptr_t *bp, const zbookmark_phys_t *zb) 216 { 217 zbookmark_phys_t czb; 218 int err = 0; 219 arc_buf_t *buf = NULL; 220 prefetch_data_t *pd = td->td_pfd; 221 boolean_t hard = td->td_flags & TRAVERSE_HARD; 222 223 switch (resume_skip_check(td, dnp, zb)) { 224 case RESUME_SKIP_ALL: 225 return (0); 226 case RESUME_SKIP_CHILDREN: 227 goto post; 228 case RESUME_SKIP_NONE: 229 break; 230 default: 231 ASSERT(0); 232 } 233 234 if (bp->blk_birth == 0) { 235 /* 236 * Since this block has a birth time of 0 it must be one of 237 * two things: a hole created before the 238 * SPA_FEATURE_HOLE_BIRTH feature was enabled, or a hole 239 * which has always been a hole in an object. 240 * 241 * If a file is written sparsely, then the unwritten parts of 242 * the file were "always holes" -- that is, they have been 243 * holes since this object was allocated. However, we (and 244 * our callers) can not necessarily tell when an object was 245 * allocated. Therefore, if it's possible that this object 246 * was freed and then its object number reused, we need to 247 * visit all the holes with birth==0. 248 * 249 * If it isn't possible that the object number was reused, 250 * then if SPA_FEATURE_HOLE_BIRTH was enabled before we wrote 251 * all the blocks we will visit as part of this traversal, 252 * then this hole must have always existed, so we can skip 253 * it. We visit blocks born after (exclusive) td_min_txg. 254 * 255 * Note that the meta-dnode cannot be reallocated. 256 */ 257 if (!send_holes_without_birth_time && 258 (!td->td_realloc_possible || 259 zb->zb_object == DMU_META_DNODE_OBJECT) && 260 td->td_hole_birth_enabled_txg <= td->td_min_txg) 261 return (0); 262 } else if (bp->blk_birth <= td->td_min_txg) { 263 return (0); 264 } 265 266 if (pd != NULL && !pd->pd_exited && prefetch_needed(pd, bp)) { 267 uint64_t size = BP_GET_LSIZE(bp); 268 mutex_enter(&pd->pd_mtx); 269 ASSERT(pd->pd_bytes_fetched >= 0); 270 while (pd->pd_bytes_fetched < size && !pd->pd_exited) 271 cv_wait(&pd->pd_cv, &pd->pd_mtx); 272 pd->pd_bytes_fetched -= size; 273 cv_broadcast(&pd->pd_cv); 274 mutex_exit(&pd->pd_mtx); 275 } 276 277 if (BP_IS_HOLE(bp)) { 278 err = td->td_func(td->td_spa, NULL, bp, zb, dnp, td->td_arg); 279 if (err != 0) 280 goto post; 281 return (0); 282 } 283 284 if (td->td_flags & TRAVERSE_PRE) { 285 err = td->td_func(td->td_spa, NULL, bp, zb, dnp, 286 td->td_arg); 287 if (err == TRAVERSE_VISIT_NO_CHILDREN) 288 return (0); 289 if (err != 0) 290 goto post; 291 } 292 293 if (BP_GET_LEVEL(bp) > 0) { 294 arc_flags_t flags = ARC_FLAG_WAIT; 295 int i; 296 blkptr_t *cbp; 297 int epb = BP_GET_LSIZE(bp) >> SPA_BLKPTRSHIFT; 298 299 err = arc_read(NULL, td->td_spa, bp, arc_getbuf_func, &buf, 300 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); 301 if (err != 0) 302 goto post; 303 cbp = buf->b_data; 304 305 for (i = 0; i < epb; i++) { 306 SET_BOOKMARK(&czb, zb->zb_objset, zb->zb_object, 307 zb->zb_level - 1, 308 zb->zb_blkid * epb + i); 309 traverse_prefetch_metadata(td, &cbp[i], &czb); 310 } 311 312 /* recursively visitbp() blocks below this */ 313 for (i = 0; i < epb; i++) { 314 SET_BOOKMARK(&czb, zb->zb_objset, zb->zb_object, 315 zb->zb_level - 1, 316 zb->zb_blkid * epb + i); 317 err = traverse_visitbp(td, dnp, &cbp[i], &czb); 318 if (err != 0) 319 break; 320 } 321 } else if (BP_GET_TYPE(bp) == DMU_OT_DNODE) { 322 arc_flags_t flags = ARC_FLAG_WAIT; 323 int i; 324 int epb = BP_GET_LSIZE(bp) >> DNODE_SHIFT; 325 326 err = arc_read(NULL, td->td_spa, bp, arc_getbuf_func, &buf, 327 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); 328 if (err != 0) 329 goto post; 330 dnode_phys_t *child_dnp = buf->b_data; 331 332 for (i = 0; i < epb; i++) { 333 prefetch_dnode_metadata(td, &child_dnp[i], 334 zb->zb_objset, zb->zb_blkid * epb + i); 335 } 336 337 /* recursively visitbp() blocks below this */ 338 for (i = 0; i < epb; i++) { 339 err = traverse_dnode(td, &child_dnp[i], 340 zb->zb_objset, zb->zb_blkid * epb + i); 341 if (err != 0) 342 break; 343 } 344 } else if (BP_GET_TYPE(bp) == DMU_OT_OBJSET) { 345 arc_flags_t flags = ARC_FLAG_WAIT; 346 347 err = arc_read(NULL, td->td_spa, bp, arc_getbuf_func, &buf, 348 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, zb); 349 if (err != 0) 350 goto post; 351 352 objset_phys_t *osp = buf->b_data; 353 prefetch_dnode_metadata(td, &osp->os_meta_dnode, zb->zb_objset, 354 DMU_META_DNODE_OBJECT); 355 /* 356 * See the block comment above for the goal of this variable. 357 * If the maxblkid of the meta-dnode is 0, then we know that 358 * we've never had more than DNODES_PER_BLOCK objects in the 359 * dataset, which means we can't have reused any object ids. 360 */ 361 if (osp->os_meta_dnode.dn_maxblkid == 0) 362 td->td_realloc_possible = B_FALSE; 363 364 if (arc_buf_size(buf) >= sizeof (objset_phys_t)) { 365 prefetch_dnode_metadata(td, &osp->os_groupused_dnode, 366 zb->zb_objset, DMU_GROUPUSED_OBJECT); 367 prefetch_dnode_metadata(td, &osp->os_userused_dnode, 368 zb->zb_objset, DMU_USERUSED_OBJECT); 369 } 370 371 err = traverse_dnode(td, &osp->os_meta_dnode, zb->zb_objset, 372 DMU_META_DNODE_OBJECT); 373 if (err == 0 && arc_buf_size(buf) >= sizeof (objset_phys_t)) { 374 err = traverse_dnode(td, &osp->os_groupused_dnode, 375 zb->zb_objset, DMU_GROUPUSED_OBJECT); 376 } 377 if (err == 0 && arc_buf_size(buf) >= sizeof (objset_phys_t)) { 378 err = traverse_dnode(td, &osp->os_userused_dnode, 379 zb->zb_objset, DMU_USERUSED_OBJECT); 380 } 381 } 382 383 if (buf) 384 arc_buf_destroy(buf, &buf); 385 386 post: 387 if (err == 0 && (td->td_flags & TRAVERSE_POST)) 388 err = td->td_func(td->td_spa, NULL, bp, zb, dnp, td->td_arg); 389 390 if (hard && (err == EIO || err == ECKSUM)) { 391 /* 392 * Ignore this disk error as requested by the HARD flag, 393 * and continue traversal. 394 */ 395 err = 0; 396 } 397 398 /* 399 * If we are stopping here, set td_resume. 400 */ 401 if (td->td_resume != NULL && err != 0 && !td->td_paused) { 402 td->td_resume->zb_objset = zb->zb_objset; 403 td->td_resume->zb_object = zb->zb_object; 404 td->td_resume->zb_level = 0; 405 /* 406 * If we have stopped on an indirect block (e.g. due to 407 * i/o error), we have not visited anything below it. 408 * Set the bookmark to the first level-0 block that we need 409 * to visit. This way, the resuming code does not need to 410 * deal with resuming from indirect blocks. 411 * 412 * Note, if zb_level <= 0, dnp may be NULL, so we don't want 413 * to dereference it. 414 */ 415 td->td_resume->zb_blkid = zb->zb_blkid; 416 if (zb->zb_level > 0) { 417 td->td_resume->zb_blkid <<= zb->zb_level * 418 (dnp->dn_indblkshift - SPA_BLKPTRSHIFT); 419 } 420 td->td_paused = B_TRUE; 421 } 422 423 return (err); 424 } 425 426 static void 427 prefetch_dnode_metadata(traverse_data_t *td, const dnode_phys_t *dnp, 428 uint64_t objset, uint64_t object) 429 { 430 int j; 431 zbookmark_phys_t czb; 432 433 for (j = 0; j < dnp->dn_nblkptr; j++) { 434 SET_BOOKMARK(&czb, objset, object, dnp->dn_nlevels - 1, j); 435 traverse_prefetch_metadata(td, &dnp->dn_blkptr[j], &czb); 436 } 437 438 if (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR) { 439 SET_BOOKMARK(&czb, objset, object, 0, DMU_SPILL_BLKID); 440 traverse_prefetch_metadata(td, &dnp->dn_spill, &czb); 441 } 442 } 443 444 static int 445 traverse_dnode(traverse_data_t *td, const dnode_phys_t *dnp, 446 uint64_t objset, uint64_t object) 447 { 448 int j, err = 0; 449 zbookmark_phys_t czb; 450 451 if (object != DMU_META_DNODE_OBJECT && td->td_resume != NULL && 452 object < td->td_resume->zb_object) 453 return (0); 454 455 if (td->td_flags & TRAVERSE_PRE) { 456 SET_BOOKMARK(&czb, objset, object, ZB_DNODE_LEVEL, 457 ZB_DNODE_BLKID); 458 err = td->td_func(td->td_spa, NULL, NULL, &czb, dnp, 459 td->td_arg); 460 if (err == TRAVERSE_VISIT_NO_CHILDREN) 461 return (0); 462 if (err != 0) 463 return (err); 464 } 465 466 for (j = 0; j < dnp->dn_nblkptr; j++) { 467 SET_BOOKMARK(&czb, objset, object, dnp->dn_nlevels - 1, j); 468 err = traverse_visitbp(td, dnp, &dnp->dn_blkptr[j], &czb); 469 if (err != 0) 470 break; 471 } 472 473 if (err == 0 && (dnp->dn_flags & DNODE_FLAG_SPILL_BLKPTR)) { 474 SET_BOOKMARK(&czb, objset, object, 0, DMU_SPILL_BLKID); 475 err = traverse_visitbp(td, dnp, &dnp->dn_spill, &czb); 476 } 477 478 if (err == 0 && (td->td_flags & TRAVERSE_POST)) { 479 SET_BOOKMARK(&czb, objset, object, ZB_DNODE_LEVEL, 480 ZB_DNODE_BLKID); 481 err = td->td_func(td->td_spa, NULL, NULL, &czb, dnp, 482 td->td_arg); 483 if (err == TRAVERSE_VISIT_NO_CHILDREN) 484 return (0); 485 if (err != 0) 486 return (err); 487 } 488 return (err); 489 } 490 491 /* ARGSUSED */ 492 static int 493 traverse_prefetcher(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, 494 const zbookmark_phys_t *zb, const dnode_phys_t *dnp, void *arg) 495 { 496 prefetch_data_t *pfd = arg; 497 arc_flags_t aflags = ARC_FLAG_NOWAIT | ARC_FLAG_PREFETCH; 498 499 ASSERT(pfd->pd_bytes_fetched >= 0); 500 if (bp == NULL) 501 return (0); 502 if (pfd->pd_cancel) 503 return (SET_ERROR(EINTR)); 504 505 if (!prefetch_needed(pfd, bp)) 506 return (0); 507 508 mutex_enter(&pfd->pd_mtx); 509 while (!pfd->pd_cancel && pfd->pd_bytes_fetched >= zfs_pd_bytes_max) 510 cv_wait(&pfd->pd_cv, &pfd->pd_mtx); 511 pfd->pd_bytes_fetched += BP_GET_LSIZE(bp); 512 cv_broadcast(&pfd->pd_cv); 513 mutex_exit(&pfd->pd_mtx); 514 515 (void) arc_read(NULL, spa, bp, NULL, NULL, ZIO_PRIORITY_ASYNC_READ, 516 ZIO_FLAG_CANFAIL | ZIO_FLAG_SPECULATIVE, &aflags, zb); 517 518 return (0); 519 } 520 521 static void 522 traverse_prefetch_thread(void *arg) 523 { 524 traverse_data_t *td_main = arg; 525 traverse_data_t td = *td_main; 526 zbookmark_phys_t czb; 527 528 td.td_func = traverse_prefetcher; 529 td.td_arg = td_main->td_pfd; 530 td.td_pfd = NULL; 531 td.td_resume = &td_main->td_pfd->pd_resume; 532 533 SET_BOOKMARK(&czb, td.td_objset, 534 ZB_ROOT_OBJECT, ZB_ROOT_LEVEL, ZB_ROOT_BLKID); 535 (void) traverse_visitbp(&td, NULL, td.td_rootbp, &czb); 536 537 mutex_enter(&td_main->td_pfd->pd_mtx); 538 td_main->td_pfd->pd_exited = B_TRUE; 539 cv_broadcast(&td_main->td_pfd->pd_cv); 540 mutex_exit(&td_main->td_pfd->pd_mtx); 541 } 542 543 /* 544 * NB: dataset must not be changing on-disk (eg, is a snapshot or we are 545 * in syncing context). 546 */ 547 static int 548 traverse_impl(spa_t *spa, dsl_dataset_t *ds, uint64_t objset, blkptr_t *rootbp, 549 uint64_t txg_start, zbookmark_phys_t *resume, int flags, 550 blkptr_cb_t func, void *arg) 551 { 552 traverse_data_t td; 553 prefetch_data_t pd = { 0 }; 554 zbookmark_phys_t czb; 555 int err; 556 557 ASSERT(ds == NULL || objset == ds->ds_object); 558 ASSERT(!(flags & TRAVERSE_PRE) || !(flags & TRAVERSE_POST)); 559 560 td.td_spa = spa; 561 td.td_objset = objset; 562 td.td_rootbp = rootbp; 563 td.td_min_txg = txg_start; 564 td.td_resume = resume; 565 td.td_func = func; 566 td.td_arg = arg; 567 td.td_pfd = &pd; 568 td.td_flags = flags; 569 td.td_paused = B_FALSE; 570 td.td_realloc_possible = (txg_start == 0 ? B_FALSE : B_TRUE); 571 572 if (spa_feature_is_active(spa, SPA_FEATURE_HOLE_BIRTH)) { 573 VERIFY(spa_feature_enabled_txg(spa, 574 SPA_FEATURE_HOLE_BIRTH, &td.td_hole_birth_enabled_txg)); 575 } else { 576 td.td_hole_birth_enabled_txg = UINT64_MAX; 577 } 578 579 pd.pd_flags = flags; 580 if (resume != NULL) 581 pd.pd_resume = *resume; 582 mutex_init(&pd.pd_mtx, NULL, MUTEX_DEFAULT, NULL); 583 cv_init(&pd.pd_cv, NULL, CV_DEFAULT, NULL); 584 585 /* See comment on ZIL traversal in dsl_scan_visitds. */ 586 if (ds != NULL && !ds->ds_is_snapshot && !BP_IS_HOLE(rootbp)) { 587 arc_flags_t flags = ARC_FLAG_WAIT; 588 objset_phys_t *osp; 589 arc_buf_t *buf; 590 591 err = arc_read(NULL, td.td_spa, rootbp, 592 arc_getbuf_func, &buf, 593 ZIO_PRIORITY_ASYNC_READ, ZIO_FLAG_CANFAIL, &flags, NULL); 594 if (err != 0) 595 return (err); 596 597 osp = buf->b_data; 598 traverse_zil(&td, &osp->os_zil_header); 599 arc_buf_destroy(buf, &buf); 600 } 601 602 if (!(flags & TRAVERSE_PREFETCH_DATA) || 603 0 == taskq_dispatch(system_taskq, traverse_prefetch_thread, 604 &td, TQ_NOQUEUE)) 605 pd.pd_exited = B_TRUE; 606 607 SET_BOOKMARK(&czb, td.td_objset, 608 ZB_ROOT_OBJECT, ZB_ROOT_LEVEL, ZB_ROOT_BLKID); 609 err = traverse_visitbp(&td, NULL, rootbp, &czb); 610 611 mutex_enter(&pd.pd_mtx); 612 pd.pd_cancel = B_TRUE; 613 cv_broadcast(&pd.pd_cv); 614 while (!pd.pd_exited) 615 cv_wait(&pd.pd_cv, &pd.pd_mtx); 616 mutex_exit(&pd.pd_mtx); 617 618 mutex_destroy(&pd.pd_mtx); 619 cv_destroy(&pd.pd_cv); 620 621 return (err); 622 } 623 624 /* 625 * NB: dataset must not be changing on-disk (eg, is a snapshot or we are 626 * in syncing context). 627 */ 628 int 629 traverse_dataset_resume(dsl_dataset_t *ds, uint64_t txg_start, 630 zbookmark_phys_t *resume, 631 int flags, blkptr_cb_t func, void *arg) 632 { 633 return (traverse_impl(ds->ds_dir->dd_pool->dp_spa, ds, ds->ds_object, 634 &dsl_dataset_phys(ds)->ds_bp, txg_start, resume, flags, func, arg)); 635 } 636 637 int 638 traverse_dataset(dsl_dataset_t *ds, uint64_t txg_start, 639 int flags, blkptr_cb_t func, void *arg) 640 { 641 return (traverse_dataset_resume(ds, txg_start, NULL, flags, func, arg)); 642 } 643 644 int 645 traverse_dataset_destroyed(spa_t *spa, blkptr_t *blkptr, 646 uint64_t txg_start, zbookmark_phys_t *resume, int flags, 647 blkptr_cb_t func, void *arg) 648 { 649 return (traverse_impl(spa, NULL, ZB_DESTROYED_OBJSET, 650 blkptr, txg_start, resume, flags, func, arg)); 651 } 652 653 /* 654 * NB: pool must not be changing on-disk (eg, from zdb or sync context). 655 */ 656 int 657 traverse_pool(spa_t *spa, uint64_t txg_start, int flags, 658 blkptr_cb_t func, void *arg) 659 { 660 int err; 661 dsl_pool_t *dp = spa_get_dsl(spa); 662 objset_t *mos = dp->dp_meta_objset; 663 boolean_t hard = (flags & TRAVERSE_HARD); 664 665 /* visit the MOS */ 666 err = traverse_impl(spa, NULL, 0, spa_get_rootblkptr(spa), 667 txg_start, NULL, flags, func, arg); 668 if (err != 0) 669 return (err); 670 671 /* visit each dataset */ 672 for (uint64_t obj = 1; err == 0; 673 err = dmu_object_next(mos, &obj, B_FALSE, txg_start)) { 674 dmu_object_info_t doi; 675 676 err = dmu_object_info(mos, obj, &doi); 677 if (err != 0) { 678 if (hard) 679 continue; 680 break; 681 } 682 683 if (doi.doi_bonus_type == DMU_OT_DSL_DATASET) { 684 dsl_dataset_t *ds; 685 uint64_t txg = txg_start; 686 687 dsl_pool_config_enter(dp, FTAG); 688 err = dsl_dataset_hold_obj(dp, obj, FTAG, &ds); 689 dsl_pool_config_exit(dp, FTAG); 690 if (err != 0) { 691 if (hard) 692 continue; 693 break; 694 } 695 if (dsl_dataset_phys(ds)->ds_prev_snap_txg > txg) 696 txg = dsl_dataset_phys(ds)->ds_prev_snap_txg; 697 err = traverse_dataset(ds, txg, flags, func, arg); 698 dsl_dataset_rele(ds, FTAG); 699 if (err != 0) 700 break; 701 } 702 } 703 if (err == ESRCH) 704 err = 0; 705 return (err); 706 } 707